Tube-sheet protector.



UNITED STATES Patented June 30,1903.

PATENT OFFICE.

TU BE'- SH EET PROTECTOR;

SPECIFICATION formingpart of Letters Patent N 0. '7 32,508, dated June 30, 1 903.

Application filed February 2, 1903 Serial No. 141,499. (No model.)

To all whom it may concern:

Be it known that 1, CHARLES H. BooNE, a

citizen of the United States, residing at San- Leandro, county of Alameda, State of California, have invented an Improvement in Boiler-Tube and Tube-Sheet Protectors; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to a device for protectingthe junction of boiler-tubes with the tube-sheets, and especially at the end most distant from the fire-box.

It consists of a tube of asbestos which may have an enlarged flange or shoulder at the end to abut against the outer face of the tubesheet and retain the supplemental tube in place.

Referring to the accompanying drawings,

Figure 1 is a front elevation and partial sec tion of a boiler with my invention attached. Fig. 2 is a front view of one of the tubes.

In the use of boilers, and especially that class in which the heat-tubes extend vertically from the fire-box upward to the upper tube-sheet, the heat of the products of combustion passing through the tubes is sogintense at the discharge end that the tubes are expanded more rapidly than the tube-sheet in the first instance, and the variable expan sion and contraction of the two soon causes asbestos or like indestructible material of low conductivity. These tubes are made of such size as to slip into the upper or outer ends of the metal tubes through which the products of combustion pass from the firebox to the chimney. In order to protect the outer end of the tube and its junction with the tube-sheet and also prevent the displacement of the supplementaltubes, I have shown a sleeve or collar 2, made of the same material and surrounding the upper end of the tube A. These collars are of sufficient thickness to rest upon the upper end of the tube and its joint with the tube-sheet, and they also extend slightly above the level of the tube-sheet, so that the products of combustion are delivered above the tube-sheet and entirely out of contact with the joint formed between the sheet and the tubes. By this construction the tube is protected from the sudden intense heat passing through it and is thus prevented from amore rapid expan- "sion than takes place in the tube-sheet, the

heat being thus gradually applied to the tube and the sheet and the expansion and contrac: tion of the two made more nearly equal. I have found by practice that this construction greatly increases the life of the tube-sheet connections and prevents leakage at this point.

Having thus described my invention, what I claim, and desire to secure by Letters Patout, is-

The combination with the metal tubes and tube-sheet of a steam-boiler, of an asbestos tube fitting each of the metal tubes and extending through the tube-sheet said asbestos tube provided with a wide collar to rest upon the end of the tube and tube-sheet.

In witness whereof Ihave hereunto set my hand.

CHAS. .H. BQONE.

Witnesses:

J. E. QUINN, JOHN W. BULEN. 

